Support adjustable in height for bicycle saddles have been known nowadays. Such devices comprise a short tube, which can be inserted in the bicycle frame and integral to the saddle on which the cyclist sits, and a blocking means, articulated to the bicycle frame and suitable to maintain the device in the configuration desired by the user.
The blocking means of the known type usually comprise a clamp, integral to the bicycle frame, on which is engaged the short tube of the saddle. The clamp is tightened around the short tube by means of a bolt and a nut.
To make the clamp opening and closing operations easier, the use of a lever, articulated to the bolt, having a length sufficient to allow the unblocking and the hand tightening of the coupling, without requiring the use of keys or of other instruments, has been known.
Practically, the set up of the saddle is obtained loosening the bolt acting on the opening lever, and lowering or rising by hand the saddle according to the necessity. One thus proceeds again to the tightening of the coupling through the lever articulated to the clamp.
The greatest drawback of these supports lays in the impossibility of varying the inclination of the saddle while the vehicle is moving.
Another drawback consists of the time wasted for the operation of adjusting the height of the saddle. Such adjustment, according to the path and the position of the cyclist, is often useful for riding the vehicle.
In fact, as it is known, during braking and stop operations or downhill riding, it is preferable to maintain the saddle in a lower position, wherein the cyclist can easily lean both feet on the ground with ease and in a safe way.
Vice versa, during the pedalling, and in particular in the uphill tracts of path, a raised position results more comfortable, wherein the cyclist can extend as much as possible the legs during the movement.
Nevertheless, because of the impossibility of performing an adjustment of the height of the saddle during the movement of the vehicle, the cyclist is forced to search for a compromise solution, setting a prefixed position before undertaking the envisaged path.
In order to try to solve the described problem, numerous solutions have been proposed, but such solutions did not achieve a wide success in the market, because of the building complications, of the high cost and of the scarce functional efficiency obtained.
For example, the Japanese patent application JP 2006154498, on behalf FUJIWARA, describes a lifting device for bicycle saddle, comprising first support means, connected at its upper part to the saddle, and second support means, connected at its lower part to the bicycle frame. Said first and second support means are linked through a couple of small arms centrally articulated to an elastic contrast member, for example a torsion spring, suitable to exert a thrust force to reciprocally put said first and second support means apart. The thrust exerted by the elastic contrast member is adjustable, for example acting on preload screw means.
Said elastic contrast member also provides suitable blocking means, controlled by hand. The blocking means are of the ratchet gear type, wherein the arrest teeth are linked to a control device, which can be controlled by the cyclist even when the bicycle is moving.
In particular, the control device is able to selectively define two positions of the blocking means: a first position suitable to allow the rotation of the central articulation in one only direction, which determines the reciprocal setting apart of the first and second support means; and a second position suitable to allow the rotation of the central articulation only in the opposite direction, which determines the reciprocal approach of the first and second support means.
Practically, when the cyclist handles the bicycle in movement, he unloads the saddle from his own weight standing up on the pedals, and acts on the control device, selecting the first position. Successively, under the thrust exerted by the elastic contrast member, the saddle moves in a raised position.
Vice versa when the cyclist is slowing down, is riding downhill or is close to the stop of the vehicle, he acts on the control device selecting the second position, remaining sitting on the saddle. In this way, the saddle lowers, moving in a lowered position, under the action of the weight of the cyclist which weighs on the saddle, which overcomes the contrast action exerted by the spring in the opposite direction.
Numerous attempts of improving the described device have been proposed. As an example, the European patent application EP 07738412.1 discloses some improvements, which concern in particular the adjustment of the force exerted by the elastic contrast member.
Nevertheless, it is observed that the de vices of the described type have some defects inherent to their particular conformation.
In fact, the solution of using two centrally articulated small arms determines a high total encumbrance of the device. This is also due to the necessity of enabling the transverse displacement of the small arms and of the central articulation block, during the axial movement of the saddle upwards or downwards.
Moreover, the central articulation block comprises costly mechanical contrivances, delicate and subject to high wear and tear. Therefore, the described device is not suitable to equip the bicycles of common use, which require cheap and robust instruments.
Japanese patent JP 53 036840 on behalf AOKI EIZOU describes a support for bicycle saddle comprising a support small rod, connected at the upper part to the saddle and engaged slidingly in a lower support element, rigidly fixed to the frame of the bicycle; an actuator member suitable to exert a thrust force on the rod in axial direction, said actuator member being housed inside said frame, at the lower part of the rod; a blocking member, integral to said lower support element and suitable to fix the position of said rod in a configuration chosen by the cyclist.
Yet, such solution has not proven to be efficient, in particular because of the conformation of the blocking member, which has not revealed to be able to block in a stable manner the vertical sliding of the rod, simultaneously ensuring an easy unblocking of the device when necessary. In other words, the described device, and the numerous variants thereof which have been proposed, have the drawback of not managing to completely block the saddle, which successively lowers when going under effect of the weight of the cyclist, or have the drawback of not allowing to easily disengage the rod when the cyclist acts on the device to vary the height of the saddle.